Gene Function

Multifunctional ATP-dependent nucleic acid helicase that unwinds DNA and RNA in a 3' to 5' direction and that plays important roles in many processes, such as DNA replication, transcriptional activation, post-transcriptional RNA regulation, mRNA translation and RNA-mediated gene silencing. Requires a 3'-single-stranded tail as entry site for acid nuclei unwinding activities as well as the binding and hydrolyzing of any of the four ribo- or deoxyribo-nucleotide triphosphates (NTPs). Unwinds numerous nucleic acid substrates such as double-stranded (ds) DNA and RNA, DNA:RNA hybrids, DNA and RNA forks composed of either partially complementary DNA duplexes or DNA:RNA hybrids, respectively, and also DNA and RNA displacement loops (D- and R-loops), triplex-helical DNA (H-DNA) structure and DNA and RNA-based G-quadruplexes. Binds dsDNA, single-stranded DNA (ssDNA), dsRNA, ssRNA and poly(A)-containing RNA. Also binds to circular dsDNA or dsRNA of either linear and/or circular forms and stimulates the relaxation of supercoiled DNAs catalyzed by topoisomerase TOP2A. Plays a role in DNA replication at origins of replication and cell cycle progression. Plays a role as a transcriptional coactivator acting as a bridging factor between polymerase II holoenzyme and transcription factors or cofactors, such as BRCA1, CREBBP, RELA and SMN1. Binds to the CDKN2A promoter. Plays several roles in post-transcriptional regulation of gene expression. In cooperation with NUP98, promotes pre-mRNA alternative splicing activities of a subset of genes. As component of a large PER complex, is involved in the negative regulation of 3' transcriptional termination of circadian target genes such as PER1 and NR1D1 and the control of the circadian rhythms (By similarity). Also acts as a nuclear resolvase that is able to bind and neutralize harmful massive secondary double-stranded RNA structures formed by inverted-repeat Alu retrotransposon elements that are inserted and transcribed as parts of genes during the process of gene transposition. Involved in the positive regulation of nuclear export of constitutive transport element (CTE)-containing unspliced mRNA. Component of the coding region determinant (CRD)-mediated complex that promotes cytoplasmic MYC mRNA stability. Plays a role in mRNA translation. Positively regulates translation of selected mRNAs through its binding to post-transcriptional control element (PCE) in the 5'-untranslated region (UTR). Involved with LARP6 in the translation stimulation of type I collagen mRNAs for CO1A1 and CO1A2 through binding of a specific stem-loop structure in their 5'-UTRs. Stimulates LIN28A-dependent mRNA translation probably by facilitating ribonucleoprotein remodeling during the process of translation. Plays also a role as a small interfering (siRNA)-loading factor involved in the RNA-induced silencing complex (RISC) loading complex (RLC) assembly, and hence functions in the RISC-mediated gene silencing process. Binds preferentially to short double-stranded RNA, such as those produced during rotavirus intestinal infection. This interaction may mediate NLRP9 inflammasome activation and trigger inflammatory response, including IL18 release and pyroptosis. Finally, mediates the attachment of heterogeneous nuclear ribonucleoproteins (hnRNPs) to actin filaments in the nucleus Source: UniProt

Relationship to CMT

Unclassified AD
1 subtype
1q25.3

First described 2023

Subtype	Inheritance	Class	OMIM	Sentinel Publication
SubtypeCMT-DHX9	Inheritanceautosomal dominant	ClassUnclassified Subtypes	OMIMn/a	Sentinel Publication Monoallelic variation in DHX9, the gene encoding the DExH-box helicase DHX9, underlies neurodevelopment disorders and Charcot-Marie-Tooth disease 2023 · 10.1016/j.ajhg.2023.06.013

Stored Identifiers

HGNC Aliases: LPK, DDX9

hgnc_idHGNC:2750

ensembl_gene_idENSG00000135829

coords_grch38chr1:182839302-182888120

coords_grch37chr1:182808504-182856886

entrez_id1660

omim_gene603115

uniprot_idsQ08211

refseq_accessionNM_030588

mane_refseqNM_001357.5

mane_ensemblENST00000367549.4

External recordsHGNC:2750OMIM 603115gnomADUniProt Q08211ClinVar P/LPMANE NM_001357.5

EvidencePanelApp Green

ClinVar Variants

Pathogenic and likely pathogenic variants in DHX9, as classified in ClinVar, are read live from NCBI. Only aggregate germline records are shown. Uncertain and conflicting classifications are not. Experts in CMT makes no claim to the accuracy of ClinVar data. This index is provided for informational purposes only.

Review stars are ClinVar’s measure of how well a classification is supported: four for a practice guideline, three for an expert panel review, two for agreement among multiple submitters, one for a single submitter with criteria provided, and none where no criteria were provided.

Reported in CMT

Reported in Other Diseases

Reported in a disease other than CMT. Listed apart rather than counted as CMT variants.

Variants w/o a Recorded Disease

Pathogenic or likely pathogenic in ClinVar, submitted without a disease recorded.

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